More Questions on 2 BK (Again)

[CoachDavidShen]

Originally Posted by jenson1a

Coach Dave

Found that post in the thread, Taming of the legs. Have copied his post

Long fins are great at taming the legs, namely taming knee flexion. It's very difficult to kick from the knee with long fins, but most important (with long fins) the swimmer will feel the flow from hip through toes or end of fin. Also promotes pointing toes not flexing tight ankles (Frankenstein feet).

A good two beat kick timing practice is to wear only one long fin on right or left foot and concentrate on single side timing and flow through toes in freestyle, i.e left hip drives down, feel energy flow through right leg through the end of fin.

Stuart

The fact that he says it is very difficult to kick from the knee with long fins... so I assumed that the long fins would promote more of the feeling of kicking from the hip.?.


Does this help?

Sherry

yes i found that via search as well. I believe his knee comment was about stopping you from kicking with excessive knee flexion, which is what we often see when people first try to kick in the water - they think of kicking a soccer ball, where they feel like they have to cock the leg at the knee to 90 degrees, and most often they cock it to the rear as if they are lining up on a soccer ball to kick it.

to kick a soccer ball with force, you will want to not only drive with the lower leg kicking out under the knee, but also drive forward at the hip as well, so the whole leg is swinging around as the bottom lower leg also snaps out from under the knee, to deliver a lot of force to a ball.

this isn't what we want in swimming. excessive knee flexion causes a lot of drag when you try to cock the leg behind you. we like to encourage a very small, compact motion with a snap of the lower leg.

now that is all only about the 2BK. when we get to something with more kicks like 6BK or just flutter kicking, you will have no choice but to move the leg with more energy at the hip because you can't just let forward motion or buoyancy of the leg bring it back up; the tempo at which you need to move the legs forces you to consciously move it back into place to be ready for the next kick.

having said the above, i have seen two styles of flutter kicking. one uses more flexion at the knee, and the other is more straight leg. I tend to teach the one with more flexion as it feels more comfortable and more natural one to me. the straight leg one requires a lot more tension to hold the leg straight and usage of muscles only at the hip to move the leg up and down - so lots of kicking from the hip there! i have seen both successfully used although i tend to favor the one with more flexion at the knee.

[CoachStuartMcDougal]

Hi David,

Thanks for clarifying this one. And yes, this was about taming excessive knee bend which is very common. Right, the legs have to be soft, not rigid to kick from the hip too - snap energy through to the toes.

Hi Sherry,

This video may help a bit more on understanding (excessive) kick from the knees vs kicking from the hip with a soft, not rigid leg: https://www.youtube.com/watch?v=NBuydZ7y7VU

Stuart

[Zenturtle]

Thats a good comparison.
For me,for really sense where the kick starts its best to concentrate on kicking with straightish legs.
The mental image of swiveling that long leg throught the resistive water anchoring the water at the top of the feet makes it logical that the work to swivel that leg is done in the core.
When I can rotate the body with that straightish leg action its only a very small step to release some tension in the knee the let the bottom leg whip a bit.
When used to straightish leg, you also feel the power of the kick decrease immedialtely when you let the knee bend too much.
So first kick with almost straight leg, and then kick with knee totally realaxed. Only the upper leg now is left to push on the water. The lower leg swivels up if any water pressure is action upon it.
At high 6BK frequencies this changes (more loose lower legs I gurss), but 2BK is relatively slow. And can be used nicely as a balance rudder too.

To (overly for some)simplify:
The motor of the leg movement is in the core, the kneejoint is only a passive joint with a rubber band on top over the knee.
Kicking with straigh leg is kicking with a stiffer rubber band over the top of the knee.

I think it also depends a lot on your ankle/hip flexor flexibility how your kick feels and how much kneebend is optimal.